title: New supraglottic airway with built-in pressure indicator decreases postoperative pharyngolaryngeal symptoms: a randomized controlled trial.
abstract: OBJECTIVE
  Excessive supraglottic airway cuff pressure increases postoperative pharyngolaryngeal symptoms such as sore throat, dysphonia, and dysphagia. A new supraglottic airway, AES Ultra CPV™ (CPV), has a built-in intracuff pressure indicator. We hypothesized that using the CPV would reduce postoperative symptoms when compared with the LMA Classic™ (LMA) without intracuff pressure guidance.
  
  
  METHODS
  Ambulatory patients undergoing general anesthesia were randomized to either CPV or LMA. A size 3/4/5 was inserted according to manufacturer guidelines. Nitrous oxide was not used. In the LMA Group, the cuff was inflated according to manufacturer's guidelines. In the CPV Group, a CPV was inserted and the cuff inflated until the indicator was in the green zone (30-44 mmHg). Intracuff pressures were measured at five minutes and 20 min post-insertion in both groups. The primary outcome was the incidence of pharyngolaryngeal symptoms, defined as sore throat, dysphonia, and/or dysphagia at one, two, and/or 24 hr postoperatively. Continuous data were compared using Student's t test and categorical data were analyzed using Chi square analysis.
  
  
  RESULTS
  The study included 170 patients, 85 per group. The mean (SD) intracuff pressure in the CPV group was significantly lower [44 (4) mmHg] than in the LMA Group [87 (37) mmHg]; P < 0.001. The incidence of pharyngolaryngeal symptoms was significantly lower in the CPV Group than in the LMA Group (26% vs 49%; P = 0.002). The absolute risk reduction was 24%, and the number-needed-to-treat was 4.3.
  
  
  CONCLUSIONS
  The incidence of postoperative pharyngolaryngeal symptoms in the CPV Group with a cuff pressure-guided strategy was significantly lower than in the LMA Group with standard practice. (
  
  
  BACKGROUND
  NCT01800344).
authors.affiliation: Department of Anesthesia, Toronto Western Hospital, University of Toronto, 399 Bathurst Street, Toronto, ON, M5T 2S8, Canada, david.wong@uhn.ca.
authors.forename: David T
authors.initials: DT
authors.lastname: Wong
authors.forename: Amanda D
authors.initials: AD
authors.lastname: Tam
authors.forename: Vanita
authors.initials: V
authors.lastname: Mehta
authors.forename: Raviraj
authors.initials: R
authors.lastname: Raveendran
authors.forename: Waleed
authors.initials: W
authors.lastname: Riad
authors.forename: Frances F
authors.initials: FF
authors.lastname: Chung
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003680:Deglutition Disorders / Q000517:prevention & control; D055154:Dysphonia / Q000517:prevention & control; D005260:Female; D006801:Humans; D017214:Laryngeal Masks / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D010612:Pharyngitis / Q000517:prevention & control; D011183:Postoperative Complications / Q000517:prevention & control*; D011312:Pressure